Foreign and finance ministers from the ten countries of the Association of South East Asian Nations (ASEAN) met in Bangkok on Saturday, setting the scene for a leaders' summit later in the day and on Sunday.
The Chinese sinking of a Philippine boat which endangered 22 Filipino fishermen is expected to put anew the South China Sea territorial conflicts under the meeting's spotlight.
Other key issues include the planned repatriation of more than 700,000 ethnic Rohingya Muslim refugees, who have fled from a violent military crackdown in Buddhist-majority Myanmar since August 2017 to neighbouring Bangladesh in a crisis that has tested ASEAN.
Critics have hit the regional bloc for failing to address the abuses in Myanmar's Rakhine state that the United Nations has called ethnic cleansing.
The 10 ASEAN countries are Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam. (ASSOCIATED PRESS)